This Blog is dedicated to all things to do with Building Information Modeling.
I'll be blogging about challenges that I come across as BIM Manager as well as points of interest that are related to BIM. Blogs on tips and technical "How-too's" to help you out with creating your BIM models correctly.
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Monday, 26 March 2012

Phasing, Phase Filter and Phase

Here is my attempt to explain Phasing and Phase Filters.. a very
complicated thing to try and explain and this is a primer to help you
understand it better.

When
encountering a project with existing construction I write a description of the
3 Phases we need for any Project, namely an existing phase for the existing
base conditions and a demolition phases for modification to existing and
construction/renovation for any changes after.The description will help explain each phase of
construction/destruction.

If were just doing New
Construction (all in one phase) the other phases are irrelevant.

If your doing New Construction in multiple Phases you can add it
here such as New construction Phase 1, New construction Phase 2 etc...

Then I add
to the Phase Filter Names to make them easier to understand.

By adding "In Current Phase" to the "Filter
Names" to remind you what you are looking at, for example: Show Previous + Demo (In Current Phase) means
that you will see the complete work in the phases preceding the active
phase...as well as demolition in this active phase.

More on this latter...

I then override the Cut Line Graphics of the Demolished Phase so
it shows up bold.

This imitates standard Architectural convention.

Currently the default is to be grayed out.

This allows me to clearly show what part of the building has been
demolished in each view.

Close this dialog box and go to your floor view.

Now you can add more Phases of New Construction, as mentioned
above, as required. Youcan also add
more Phase Filters but we have found that given the 7 combinations that Revit
gives you is more than adequate.

Now that we have established the Project Phase it's time to look
at how to apply them to our views.

If you are doing a Renovation/Addition project you'll need to
create multiple Duplicate Views. We
do this so we can easily represent each phase (Existing, Demolition and New
Construction) on each view.

We also need to set the Phasing
for each view.

Here is an example of how the View and the Phase Filters and Phase
selections are used.

Existing View

With any Renovation/Addition project you need to know what ExistingBuilding
you are dealing with, in this View you'll draw the existing building.

Your Existing View Phasing should be set as follows.

Phase Filter will be set to Show New, only because there is no
previous phase.

The Phase is Existing
because that's what your currently creating, so an existing building in the
real world is "New Construction" in "Existing"
Phase....confusing I know!

Existing View show the existing
building.

Once you have the existing building modeled, Duplicate the view
and rename it to Demolition.

Demolition View

This view you'll use the little hammer icon on the Phasing panel
on the Manage Tab and hit the stuff that is to be demolished. Duh!

Notice that if your demolishing an existing wall that has doors or
windows you will have to demolish those as well (if they're being demolished as
well that is).

Your Demolition View Phasing should be set as follows.

Phase Filter will be set to Show Previous + Demo, as you want to
show the Previous phase which is Existing and the Demolition occurring in the
active "Demolition" phase.

The Phase is Demolition
because that's what your currently creating.

Demolition View show the
existing building and any components of the existing building that are to be
Demolished.

Once you have the Demolished view created duplicate the view and
rename it to New Construction.

New Construction
View

This view you'll start placing walls and components that are part
of the projects New Construction.

Your New Construction View
Phasing should be set as follows.

Phase Filter will be set to Show Previous + New, as you want to show
the Previous phase which is what will be remaining of the ExistingBuilding
minus the Demolition as well as the New construction.

What is shown in "Show Previous" is the "Completed
work" for all phases preceding the current phase. So what we are looking
at is Existing (completed) and Demolition (completed) plus New Construction.

The Phase is New
Construction because that's what your currently creating.

New Construction View should
clearly show the New construction as well as the existing building after
demolition has occurred.

Note:Any model objects you create while in a
specific Phase will be part of that Phase, thus controlled by the Phase
filters.

Filters not only apply to Plan Views but also too your other views
including Sections, Elevations and also 3D Views.

When you Shade the view the Material assigned to the Phase Status now comes into to play.

If you look Under Materials you'll find phase materials for each
Phase. These Materials have colour
shading assigned to them to clearly show each phase.

Also... Thanks Adam for reviewing this document for me and adding your
thoughts. I felt it to be such a difficult subject to document, I appreciate Adams
input.

You cannot add new Phase Status.When I first started using phases as phase filters I too wanted to create a new Phase Status, however what I found was that the phase status that were given to us works fine.

What I found was that for each situation the combination of the Phase Filters and Phases covers just about all situations.

Adding a "Demolition" phase isn't typically needed. You can demolish elements in the New Construction phase and use the Show Previous + Demo phase filter for the demolition plans. Adding an extra phase for Demolition is just making things more complicated. You would only create a Demolition phase if it was indeed a separte distinct set of drawings that was needed.

Adding this phase can actually cause confusion. If you were only demolishing a door or a window in a wall, Revit will add in a filler wall. On your construction plan, this infilled wall will look existing (because it was created in a previous phase). When in fact it should appear new in the New Construction Phase.

I wanted exactly the same thing when I first started to use Phases and Phase Filters... it took me a while to fully understand how to use them effectively but when I did I realized I didn't actually need anymore categories.You cant actually create new phases, I asked Autodesk.

Between all the phases and phase filters you should be able to graphically show what you need to represent.... or you could use worksets as an alternative, or design options??

Sent this to my good friend Eddy in Calgary who is my MEP expert, here's his reply: That’s an interesting question!! I played around with this for a while and I was able to move individual devices from phase to phase without issue. I was also able to move entire electrical systems from phase to phase successfully. Obviously when items were demolished they would lose connection which is expected.

Scott, we just came across something, we are a structural firm and are working with an arch. In our model we have both existing and new elements. They are on the right phase. But when the arch links our model into theirs, they say everything in our model shows up as existing in theirs. I am confused. Is it an Arch issue?

I a friend of mine who is my Revit Structure "go to guy", Mike from Bush-Bohlman here in Vancouver. Below are Mikes thoughts.

Without actually seeing the workflow my first thoughts are that it is a link setting or adjustment. When the Architect links in the structural model the view visibility settings for the Revit link display should be set to “by linked view” and by entering that dialogue box the structural link display should be as intended. If this doesn’t provide the desired settings the link could be set to custom and manipulated as desired.

I'm working on a Phase II of a project, Phase I of which was completed last year. Is there any way to use the previous drawing set and "convert" the New Construction elements into Existing Elements, to that I don't have to create and additional Phase within the file? Since the work was completed long ago, what had been shown as New is now actually Existing. Thanks in advance for any help you can offer!

I found this solution written by Cadastrophe (a fellow EE member) in a Revit Foum.

Two possible methods (neither of which is one-command):

1. Create a Multi-Category Schedule, select any one field, and disable "Itemize all instances". This should leave one cell; select it and click "Highlight in Model" on the Ribbon. Under Properties, the Phase parameters should be available but if not, use the Selection Filter to remove the non-applicable elements (such as Detail Items).

2. Go to Phases, create a New "New Construction" Phase at the end, select the original "New Construction" Phase and under 'Combine with:' click "Previous". This will move all of the Model Elements to the "Existing" Phase, but it will also set ALL of your Views to the Existing Phase as well.

Also check out this blog that does an excellent job of explaining phases. http://revitclinic.typepad.com/my_weblog/2008/10/time-to-phase.html

Hi! I was wondering: is there a way to subdivide elements (walls, slabs) and automatically assign phases to them using grid lines (or lines) underneath the 3D model (i.e. "divide elements")? This creates "parts", but unfortunately all these parts or subdivisions are assigned the same phase. So either: (1) the subdivision needs to be more complete, creating independent elements instead of parts of a whole or (2) the parameter "phase" Needs to replaced with a parameter that applies to individual "parts". Basically, we're looking for a way to create subdivisions of elements to define construction / formwork phases in as few steps as possible. Currently, we have to create a new model (one slab becomes 10 or more sub-slabs), which is time-consuming. Other ideas: assigning materials to subdivisions, using Dynamo to generate subdivisions, using other program (Navisworks, iTWO) as second step...

Hi Scott, Thank you for giving such a good explanation of the phasing process. I was struggling to get understand how it all works and then i came across your page. I am struggling with a few things and it would be great if you could help me out. 1. the new walls and floor are appearing to be translucent. Is that how it's meant to be when the project is divided into phases? 2. How can i make then non translucent? I tried going to phases tab and then onto to graphics override and play around with the transparency there. Then back onto phase filters and overriding the graphics but it turns the whole model into a black mass. :/

About Me

Scott Chatterton is the BIM and Quality Control Manager for HDR|CEI. Scott has over 25 years of industry experience and has a long history of using Autodesk products as an architectural technician, Autodesk-certified AEC instructor, CAD manager, and now as a BIM and Quality Control manager.
Scott has experience as an authorized, certified Instructor of the Revit and AutoCAD product line, specializing in architectural design, and is currently a certified professional in both Revit and AutoCAD and building performance analysis.
Scott’s extensive knowledge enables him to create and apply efficient design and construction practices using the latest BIM technology and techniques. As a result of his experience, Scott is a sought-after author and presenter at BIM-related conferences, addressing ideas on BIM workflow, processes and protocols.
Scott is also on the board of directors for the Canada BIM Council, a member of the advisory board for various education institutions such as Thompson Rivers University, and a BIM adviser for Okanagan College, Southern Interior Construction Association, Athabasca University, and Vancouver College.